The Organization of the Muscle

The muscle hierarchy procedes as follows from largest to smallest: Muscle, Fascicle, Muscle Fiber and Sarcomere. Each individual muscle is an organ surrounded by a layer of connective tissue, called the epimysium, which thickens into a tendon and then attaches to the periostium of a bone. Each muscle is composed of a grouping of fasicles, which is composed of a bunch of muscle cells, also called muscle fibers. Each muscle fiber is long and has multiple nuclei and specialized organelles called sarcomeres. The sarcomere is the contractile unit of the muscle.
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For more information on muscles, particularly the skeletal muscle anatomy, visit
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